Suppressors are used to suppress the muzzle blast of a firearm. A typical suppressor is mounted on the distal end of the muzzle and defines a projectile passage extending along an axis. The projectile passage is aligned with the bore of the muzzle so that the fired round travels through the projectile passage after exiting the muzzle. A shroud typically encloses the projectile passage, and one or more baffle walls extend inward from the shroud and around the projectile passage. The baffle walls are oriented transverse to the axis of the projectile passage to define expansion chambers in fluid communication with the projectile passage. At least some of the blast gas associated with the fired round expands radially into the expansion chambers. The baffles thereby entrap and slow some of the blast gas so that the blast gas exits the suppressor at a lower velocity than it would have exited the muzzle of the firearm if no suppressor were used. The suppressor thereby reduces the energy of the blast gas to reduce the report (i.e., suppress the sound) of the round.
One type of suppressor includes a shroud, proximal and distal end caps secured to the shroud, and a plurality of baffle cups stacked together in the interior of the shroud between the proximal and distal end caps. Each baffle cup includes a baffle wall oriented transverse to the axis of the shroud and a spacer portion that extends axially from the baffle wall. When the baffle cups are stacked together inside the shroud, the spacer portion engages an adjacent baffle cup to maintain spacing between the baffle walls of the adjacent baffle cups. The baffle walls and the end caps define a plurality of expansion chambers along the length of the suppressor for receiving blast gas, which reduces the velocity at which the blast gas exits the suppressor and thereby reduces the report of the round.